dtc: Make make print a message when linking testcases

Currently, dtc relies on make's implicit rule to build the testcases.
This means that when not making verbosely (V=0, the default) there is
no message at all while relinking the testsuites.  This can be very
confusing when updating libfdt.a (upon which the testcases depend) and
make appears to do nothing.

This patch corrects the situation, borrowing the rule used to link dtc
itself to link all the testcases as well.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Makefile

@@ -101,8 +101,6 @@ lex.yy.c: dtc-lexer.l
 	$(LEX) $<
 
 dtc: $(DTC_OBJS)
-	@$(VECHO) LD $@
-	$(LINK.c) -o $@ $^
 
 ftdump:	ftdump.o
 
@@ -168,6 +166,10 @@ endef
 #
 # Generic compile rules
 #
+%: %.o
+	@$(VECHO) LD $@
+	$(LINK.c) -o $@ $^
+
 %.o: %.c
 	@$(VECHO) CC $@
 	$(CC) $(CPPFLAGS) $(CFLAGS) -o $@ -c $<